This section provides background information related to the present disclosure which is not necessarily prior art.
Serpentine accessory drive systems for automotive vehicles are commonly used to transfer power, via associated pulleys, from an internal combustion engine crankshaft to accessory components such as alternators, water pumps, power steering pumps, and air conditioning compressors. Under operating conditions where the crankshaft slows suddenly, high-inertia components of the accessory drive will tend to load the serpentine belt such that the belt may squeal or slip, and/or vibrate, and/or cause the tensioner and/or accessory components to vibrate.
It is known to counter this effect with an over-running decoupler, which may be positioned on one of the high-inertia components or on the engine crankshaft. Examples of such devices are disclosed in U.S. Pat. Nos. 7,618,337; 7,591,357 and 7,624,852. While such devices are well suited for their intended purpose, we have noted that it would be desirable to lock, bypass or otherwise transmit rotary power through the over-running decoupler in some situations. One such situation involves a BAS (i.e., “belt-alternator-starter”) system in which a belt-driven alternator may be operated as a starter motor that will provide rotary power to the serpentine belt for rotating the crankshaft during starting of the internal combustion engine.
An overrunning-enabled automotive starter generator is disclosed in International Publication No. WO 03/104673 (International Application No. PCT/CA03/00852) published Dec. 18, 2003. While such device is suited for its intended purpose, there remains a need in the art for an improved clutched device.